(CNN) -- A city official in the remote Brazilian Amazon village of Envira told CNN that five members of the Kulina tribe are on the run after being accused of murdering, butchering and eating a farmer in a ritual act of cannibalism.

The village's chief of staff, Maronilton da Silva Clementino, said Kulina tribesmen took the life of Ocelio Alves de Carvalho, 19, last week on the outskirts of Envira, which is in the far western part of Brazil that bumps up against Peru.

Portal Amazonia newspaper reported that the Indians escaped after being held for a few hours in the city's police station.

No arrest warrants were issued. Brazilian law does not allow the military or civil police to enter Indian lands, Portal Amazonia reported.

It is still unknown how many people took part in the alleged cannibalistic ritual, although several Indians have fled into the jungle fearing prosecution, the newspaper Diario do Amazonas reported.

Clementino said the victim was herding cattle when he met with a group of Indians who invited him back to their village.

"They knew each other and they sometimes helped one another. They invited him to their reservation three days ago and he was never seen again," Clementino said.

"The family decided to go into the reservation and that's when they saw his body quartered and his skull hanging on a tree. It was very tragic for the family," he said.

The news of the incident came from the Indians themselves, who apparently bragged about eating the man's organs, Clementino said.

Members of the tribe told residents of Envira -- where 190 Kulina families brush shoulders with non-tribal Brazilians -- that they held a cannibalistic ritual in which they cooked the victim's organs, Clementino said.

He said Kulina Indians began surrounding the police station where the suspects were briefly interrogated.

Villagers told authorities they are incensed by the lack of response from FUNAI, Brazil's National Indian Foundation.

"The family is very frustrated with the law here, which protects the Indians and doesn't help protect us," he said. "They start drinking and local farmers here are afraid who could be next."

He said the man's family are upset that authorities did not arrive until three days later. But a FUNAI official told the newspaper Voz do Acre that access to Envira is very difficult, requiring long boat or helicopter rides.

According to FUNAI, about 2,500 Kulina live in Brazil's Acre state, which borders with Peru, where 450 Kulina live. This remote jungle corridor is known for its isolated tribes.

The Kulina are classified as an "isolated" tribe but some have contact with the non-indian population.

The Kulina are also known for their complex language. FUNAI studies show that Kulina women speak a completely different language from the men.

According to FUNAI, there are 460,000 Indians in Brazil and 1,300 indian languages. There are 55 groups considered to live in isolation.